1. Field of the Invention
The present invention relates to a device for controlling the recirculation of exhaust gases in an internal combustion engine.
2. Description of the Prior Art
It is well known to use devices for the recirculation of exhaust gases in internal combustion engines to reduce atmospheric pollution. A recirculation passage reintroduces the exhaust gases into the air-fuel mixture of the intake manifold of the engine so as to reduce the polluting emissions of nitrogen oxides.
A valve for controlling the recirculation is generally placed in the recirculation passage to control the recirculation flow in response to the vacuum created by the engine in the intake manifold.
To obtain a high rate of recirculation in the full range of engine operation, it has proven to be essential to adapt the rate of recirculation to the capacity of the engine to accept recirculated gases without reduced engine performance at low loads and without, consequently, increasing the emissions of hydrocarbons.